In 1951, an era of atomic testing in the Nevada desert began as an Air Force plane dropped a one-kiloton bomb on Frenchman Flats.

In 1967, more than 60 nations signed a treaty banning the orbiting of nuclear weapons.

In 1973, the Vietnam peace accords were signed in Paris.

In 2001, two Dartmouth College professors, Half and Susanne Zantop, were murdered at their home by two teenagers. (Robert Tulloch is serving life in prison without parole; James Parker is serving 25 years to life.)

Ten years ago: Switzerland’s ambassador to the United States, Carlo Jagmetti, resigned after outraging Jewish groups and their supporters by likening his country’s Nazi gold crisis to a war that had to be won.

Five years ago: Wafa Idris, a Palestinian paramedic, became the first female suicide bomber against Israel; her victim was an 81-year-old man. A munitions depot in Nigeria exploded; more than 1,000 people died, most of them drowning in a nearby canal during the resulting stampede. The Super Bowl matchup was decided as the New England Patriots upset the Pittsburgh Steelers 24-17 to win the AFC championship and the St. Louis Rams defeated the Philadelphia Eagles 29-24 to win the NFC championship. Thomas Johansson defeated Marat Safin 3-6, 6-4, 6-4, 7-6 (4) to win the Australian Open final.

One year ago: Western Union delivered its last telegram. In the wake of Hamas’ triumph in Palestinian parliamentary elections, thousands of outraged Fatah supporters burned cars and fired in the air across the Gaza Strip. The first inhalable version of insulin, “Exubera,” won federal approval.

Thought for Today: “If we die, we want people to accept it ... We are in a risky business and we hope that if anything happens to us, it will not delay the program. The conquest of space is worth the risk of life.” — Virgil I. “Gus” Grissom (1926-1967).